Industrialization Drives a Late‐19th‐Century Pulse in Appalachian Fire Activity

Aim Fire has long influenced forests in the Appalachian Mountains of eastern North America, but the extent to which 19th‐century industrialization reshaped regional fire regimes remains less understood. We evaluated whether industrial‐era fire activity represented a statistically extreme departure from longer‐term variability and examined how fire activity was organized across the region during and after industrialization. Location Appalachian Mountains, USA. Taxon Pinus spp. Methods We compiled tree‐ring fire‐scar records from 66 Appalachian sites and analyzed annual network fire occurrence using a core network of 32 sites with sufficient temporal coverage between 1800 and 1950. We identified regime shifts in regional fire activity, evaluated relationships with reconstructed drought variability, examined spatial patterns of shared fire years among sites, and mapped post‐1950 fire persistence across the broader network. Results Network fire occurrence increased during the late 19th century before collapsing during the early 20th century. Elevated fire activity coincided with rapid railroad expansion and broader industrial‐era land‐use change. Fire activity remained associated with drought throughout the record, but the timing and magnitude of the industrial‐era fire pulse aligned more closely with industrialization and subsequent fire suppression than with shifts in reconstructed climate variability. Analyses of shared fire years among sites indicated weak spatial structuring, suggesting that elevated regional fire activity reflected geographically widespread human ignitions across heterogeneous landscapes. Post‐1950 fire persistence was concentrated within the Pennsylvania anthracite and southern West Virginia coal regions. Main Conclusions Industrialization coincided with a regional pulse in Appalachian fire activity characterized by widespread human ignitions associated with industrial‐era land use, while climatic variability continued to modulate fire activity through time. Persistent fire activity within Appalachian coalfield regions further suggests that industrial and post‐industrial land‐use legacies contributed to the uneven decline of fire activity during the suppression era.